Ledbetter said although nearly all of Cornwall received its water from Colliford Lake, South West Water had bought a former china clay quarry near St Austell.
He said: “We’ve recently brought in Blackpool Quarry, which is an old quarry pit, which we are using as a kind of bucket to store water to really provide extra resilience, too.
“We do have two or three of those already that help supply water and we know that they are a really good way of storing water because the clay pits themselves are excellent because they basically don’t leak.”
Ledbetter said there had been “challenges” with securing environmental permissions for a proposed desalination plant in Par.
“It could be that desalination comes back into the equation, but at the moment we’re reviewing across all the different types of options we could be looking at,” he added.
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